Save your data and use a copy for this exercize...........
Assuming you don't actually have any leading zeros.........
Highlight your column with the phone numbers and do Edit > Replace > in the
"Find what:" box type just a period > in the "Replace with:" box leave it
blank > press the Replace All button...........
Then, highlight the column again and do Right-click > Format cells >
NumberTab > Special > and choose "Phone Number" in the "Type:" window > OK
Vaya con Dios,
Chuck, CABGx3